A client computer system can request an application from a server computer system. Such a request can be transmitted remotely, such as via the Internet, or issued locally, such as within local area network. In a runtime system, the requested application may depend on classes, methods, data fields, and resources created by other developers. These classes, methods, data fields, and resources may be referred to as “types” and are often packaged together with other types into collections called “libraries”. In existing approaches, the server sends the application to the client, in response to the client's request. In addition, any statically recorded libraries associated with the application must also be sent and loaded on the client.
Typically, a statically recorded library is a unit of distribution for these types. However, all of the types in a library may not be required by a given application. For example, a given application may depend on only a single type from a given library. As such, the unneeded types in a library can waste system resources when the entire library is loaded on a client system. Wasted resources are of particular concern in compact devices, such as mobile phones and PDA's (personal digital assistants).
In addition, distributing a library to a client system can require considerable bandwidth. For example, if a client system downloads via the Internet an application and associated libraries on which the application depends, the download time and the network resources required to perform the download are often nontrivial. Furthermore, the library or individual types within the library may already be loaded on a client system, which makes the downloading of the entire static library to the client unnecessary.
Furthermore, as resources within the client system become limited, a user traditionally must selectively delete files, including applications and libraries, from the client system to make room for new applications and libraries. However, it is difficult for a user to determine which applications and libraries are expendable. Furthermore, many libraries are shared by multiple applications. As such, it is difficult for a user to keep track of the dependencies required to safely delete unwanted libraries without disabling an essential application.